Installing LED/Analog Vu Meter to Front Panel

[zkool448]

Definitely no McIntosh here, but a proudly handmade Bijou case which also has a meter

(*note feet are not permanently installed)

 

[linuxworks]

that works well. blue 'works' there, I think.

super job.

the photo also has a soft feel to it. so, good on the photo, too

 

[DKJones96]

Very clean look, great job!

 

[zkool448]

I luv it when it 'works' for linuxworks!

Thanks Kyle!

 

[dbfreak]

That turned out excellent! Who sells analog VU meters like that?

 

[zkool448]

I got the analog VU from a fellow headfi'er here in Toronto (thanks zare). I think these VU's are made by a company called Flashstar in Asia but zare can confirm this.

edit: Just did a google and found this linky (check page 3). cheers.

 

[dbfreak]

Thanks much!

 

[sachu]

Quote:

Originally Posted by zkool448 /img/forum/go_quote.gif Definitely no McIntosh here, but a proudly handmade Bijou case which also has a meter

You seriously have outdone yourself Joel. Man I am at a loss for word. Brilliant

Masterpiece!

errmmm..what next?...an EHHA to complete the Cavalli audio line up?

 

[akcrusier]

I know this is a bit off topic but I was wondering where zkool448 sourced those feet? I have been looking all over for some like those at a reasonable price.

 

[linuxworks]

Quote:

Originally Posted by zkool448 /img/forum/go_quote.gif I got the analog VU from a fellow headfi'er here in Toronto (thanks zare). I think these VU's are made by a company called Flashstar in Asia but zare can confirm this. edit: Just did a google and found this linky (check page 3). cheers.

we might need a group buy (?). I bet there is going to be a little interest in getting some dual meters like this

I wonder if its easier to mount a dual or just mount 2 singles?

even though its not needed at all, it really does add a touch of something to the front. it fills the front space up and gives interest. I really like it

 

[zkool448]

Quote:

Originally Posted by sachu /img/forum/go_quote.gif You seriously have outdone yourself Joel. Man I am at a loss for word. Brilliant Masterpiece! errmmm..what next?...an EHHA to complete the Cavalli audio line up?

lol I'm waiting until after the Colorado meet to hear some impressions between the EHHA vs the Bijou before I make any plans first

Quote:

Originally Posted by akcrusier /img/forum/go_quote.gif I know this is a bit off topic but I was wondering where zkool448 sourced those feet? I have been looking all over for some like those at a reasonable price.

The case feet I'm using are quite reasonably priced, I got them off eBay. Here's the link.



Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif we might need a group buy (?). I bet there is going to be a little interest in getting some dual meters like this I wonder if its easier to mount a dual or just mount 2 singles? even though its not needed at all, it really does add a touch of something to the front. it fills the front space up and gives interest. I really like it

I'm really glad I installed one on mine. I really like the look of it. They'd go really nice especially if installed on a buffalo32/source of some sort.

Which is easier? I think mounting either a dual or two single would probably be the same, however the round ones are possibly the easiest.

I heard from zare that dealing with the meter vendors from overseas was quite a nightmare so a group buy would probably difficult to do.

 

[Voodoochile]

So much nicer with analog meters than leds, especially with a tube amp.

 

[zare]

Quote:

Originally Posted by zkool448 /img/forum/go_quote.gif I heard from zare that dealing with the meter vendors from overseas was quite a nightmare so a group buy would probably difficult to do.

Well, did order some samples from here, but communication was poor and the shipping cost is more then the meters. Also they have sent me the wrong once with excuse: we did not have that color in stock.
Anyhow, I have some ST-160 and ST475 from here for the F4 and F5 passlabs builds. This company was much better to work with. I might have some extra to share if anyone is interested.

Gjorgji

 

[shldn]

Hi Guys,

I would like to implement analog vu meters on my power amp front panel and so far i've got Rod Elliott's circuit working satisfactory.

However if calibrated properly, at normal listening volume the meters will have little to no needle movement as amb says,
Quote:

Originally Posted by amb /img/forum/go_quote.gif For a meter to be of practical use (rather than just as visual amusement), 0dB would need to be calibrated to the maximum rated output power of the amp. Let's take the β24 as an example, 0dB would be around 180W into 8 ohms. On a conventional analog "VU" meter, the meter needle would hardly move when the amp is putting out 1.8W, and that's usually already a fair amount of sound pressure level on most speakers. If you crank up the sensitivity of the meters to show movement at low/mid volumes, then the meter would simply peg on the right hand stop when the amp is called upon to deliver more of its power (not to mention that the meter then ceases to "measure" anything meaningful).

How can i implement something like a toggle switch on the above circuit to switch between vu mode and another mode that just samples the music playing to indicate needle movement for visual amusement.

What is required for this, a buffer before the circuit or

Quote:

Originally Posted by amb An analog meter like that could only be achieved with a special meter drive circuit that has compressive gain.

Any links/schematics for this kind of compressive/adaptive gain circuit or something i can adapt to for this purpose? linuxworks has mentioned CPUs, but CPUs and firmware/software is not my forte.

 

[amb]

shldn, one way to do it is to use a logarithmic amplifier to drive the meters, in order to expand its dynamic range (google "logarithmic amplifier" and you'll find examples and even specialty chips that implement this characteristics), but doing so will render the dial markings on your meter meaningless.

The other option is to simply have switchable gain characteristics, so that "0dB" would correspond to full power or 1/10th power (or even 1/100th power if you use a 3-position rotary switch), and calibrate each position separately. Sort of like changing gears.